Finnish mythology is a little known mythology internationally. The best known part of it is, without question, the national epic of Finland: Kalevala.
Kalevala was collected by Elias Lönnrot during the 19th century. He travelled across Finnish countryside, mainly in Eastern Finland, collecting traditional poems and folktales. At this time not much of Finnish mythology had been written down, which is one of the reasons why Kalevala has gained such a huge cultural significance to Finns; it is one of those rare pieces of writing that's recorded Finnish traditions from the pagan times.
When Lönnrot left for his journey, he hoped or believed that he would find this full epic from somewhere there, from the countryside. That Finns would have a similar complete story still circulating as oral tradition, one comparable to the likes of Iliad and Odyssey. He was incorrect, of course. There was a lot of oral tradition alive, yes, but they didn't form a complete story. In fact, the little tales where connected to each other loosely at best, most didn't have anything to do with each other. But Lönnrot had decided to collect the Finnish epic and that's what he'd do, even if that meant taking massive creative liberties in its creation process.
As much as Kalevala is praised as this great work of Finnish mythology (and don't get me wrong, it is pretty great) huge portions of it were actually invented or heavily modified by Lönnrot himself. As there was no specific timeline for the events, he was free to make up his own. He'd connect originally independent tales together and invent completely new ones in order to turn Kalevala into a more comprehensive collection.
While this is not a secret, surprisingly many individuals - foreign and Finnish alike - are unaware of it. On top of that, it is virtually impossible to get accurate information on the Finnish mythology in English, online or otherwise. And no, never EVER use Wikipedia as a source for Finnish mythology. Most of the information on Finnish mythology on there is incorrect. And thus, Kalevala becomes one of the only English sources one can use to get even remotely accurate infomation on the Finnish myths.
For Finns, the situation is a bit different. (As in, you have no excuse.) There is an amazing online resource for any Finnish-speaking individual who wants to read up some oral tradition, called Suomen kansan vanhat runot ("Old poems of the Finnish people") or SKVR for short. Whether it's stories, proverbs, spells or children's songs, there is a massive collection of them on SKVR's website (https://skvr.fi/).
And this brings us to the creation myth explained in the beginning of Kalevala. The air goddess named Ilmatar laid down to sleep on the bottom of the Primordial Sea, but her knee remained atop the surface. A goldeneye laid seven eggs on the knee that eventually fell down and broke. The broken pieces of the eggs formed different parts of the world, such as the sky and land. The moon is born out of the yolk and the sun of the white. Later, Ilmatar gives birth to a wise, old man named Väinämöinen who becomes an important character in the epic.

Ad Astra by Akseli Gallen-Kallela is my favourite Ilmatar.
This version from the Finnic poems isn't as well known as Kalevala's version. I find it unfortunate as I think I prefer this "original" one. It brings an interestic dualistic element to Finnish mythology that you can't find from many of the other folktales. Also, some stories speak of the two as brothers, both born of the mysterious maiden Iro (though Iro was most likely a later invention). Kind of gives this Marvel's Thor and Loki element to the whole thing. Marvel's specifically, as Thor and Loki weren't brothers in Norse mythology. Or would Cain and Abel be a better comparison?
So there you have an example of some of the modifications made to Kalevala as compared to the folk poems. I wanted to share it as I really quite like the dualistic elements of the folk poetry version. Also, there isn't enough info on Finnish mythology on the Internet in my humble opinion.
Note: There are female spirits of air in Finnish mythology that you could call "ilman immet" or "ilmattaret". However, the specific capital I Ilmatar mentioned in the beginning of Kalevala is a Kalevala Original Character.
Also, one more time: don't believe the Wikipedia articles on Finnish mythological figures...
Kalevala was collected by Elias Lönnrot during the 19th century. He travelled across Finnish countryside, mainly in Eastern Finland, collecting traditional poems and folktales. At this time not much of Finnish mythology had been written down, which is one of the reasons why Kalevala has gained such a huge cultural significance to Finns; it is one of those rare pieces of writing that's recorded Finnish traditions from the pagan times.
When Lönnrot left for his journey, he hoped or believed that he would find this full epic from somewhere there, from the countryside. That Finns would have a similar complete story still circulating as oral tradition, one comparable to the likes of Iliad and Odyssey. He was incorrect, of course. There was a lot of oral tradition alive, yes, but they didn't form a complete story. In fact, the little tales where connected to each other loosely at best, most didn't have anything to do with each other. But Lönnrot had decided to collect the Finnish epic and that's what he'd do, even if that meant taking massive creative liberties in its creation process.
As much as Kalevala is praised as this great work of Finnish mythology (and don't get me wrong, it is pretty great) huge portions of it were actually invented or heavily modified by Lönnrot himself. As there was no specific timeline for the events, he was free to make up his own. He'd connect originally independent tales together and invent completely new ones in order to turn Kalevala into a more comprehensive collection.
While this is not a secret, surprisingly many individuals - foreign and Finnish alike - are unaware of it. On top of that, it is virtually impossible to get accurate information on the Finnish mythology in English, online or otherwise. And no, never EVER use Wikipedia as a source for Finnish mythology. Most of the information on Finnish mythology on there is incorrect. And thus, Kalevala becomes one of the only English sources one can use to get even remotely accurate infomation on the Finnish myths.
For Finns, the situation is a bit different. (As in, you have no excuse.) There is an amazing online resource for any Finnish-speaking individual who wants to read up some oral tradition, called Suomen kansan vanhat runot ("Old poems of the Finnish people") or SKVR for short. Whether it's stories, proverbs, spells or children's songs, there is a massive collection of them on SKVR's website (https://skvr.fi/).
And this brings us to the creation myth explained in the beginning of Kalevala. The air goddess named Ilmatar laid down to sleep on the bottom of the Primordial Sea, but her knee remained atop the surface. A goldeneye laid seven eggs on the knee that eventually fell down and broke. The broken pieces of the eggs formed different parts of the world, such as the sky and land. The moon is born out of the yolk and the sun of the white. Later, Ilmatar gives birth to a wise, old man named Väinämöinen who becomes an important character in the epic.

Ad Astra by Akseli Gallen-Kallela is my favourite Ilmatar.
So that's a pretty simple story. Ilmatar is a character who has appeared quite a bit in art, music, literature etc. Too bad that she isn't actually a character from the Finnish mythology but Lönnrot's invention.
It's not possible to say what is "the real" Finnish creation myth as there are different regional variations of it, but most of them go something along the lines of this: Even before the creation of the world there existed some semi-divine creatures. Some of them were the wise sorcerer Väinämöinen and his nemesis, the young and rash Joukahainen. Joukahainen envied Väinämöinen's skills in magic and challenged him to a duel (of spellcasting or swordfighting, depends on the version). Väinämöinen wins and, hungry for revenge, Joukahainen shoots him down as he is riding on the sea. Väinämöinen plunges into the water with only his knee remaining atop the surface, a goldeneye lays eggs on it, the eggs break, you know how the story goes.This version from the Finnic poems isn't as well known as Kalevala's version. I find it unfortunate as I think I prefer this "original" one. It brings an interestic dualistic element to Finnish mythology that you can't find from many of the other folktales. Also, some stories speak of the two as brothers, both born of the mysterious maiden Iro (though Iro was most likely a later invention). Kind of gives this Marvel's Thor and Loki element to the whole thing. Marvel's specifically, as Thor and Loki weren't brothers in Norse mythology. Or would Cain and Abel be a better comparison?
So there you have an example of some of the modifications made to Kalevala as compared to the folk poems. I wanted to share it as I really quite like the dualistic elements of the folk poetry version. Also, there isn't enough info on Finnish mythology on the Internet in my humble opinion.
Note: There are female spirits of air in Finnish mythology that you could call "ilman immet" or "ilmattaret". However, the specific capital I Ilmatar mentioned in the beginning of Kalevala is a Kalevala Original Character.
Also, one more time: don't believe the Wikipedia articles on Finnish mythological figures...